Editing Self-propelled anti-aircraft weapon (section)

===World War II===
{{Unreferenced section|date=November 2024}}[[File:Niemieckie samobieżne działo przeciwlotnicze "Wirbelwind" (2-426).jpg|thumb|left|German ''Flakpanzer IV "[[Wirbelwind]]"'' - a [[2 cm Flak 30/38/Flakvierling#2 cm Flakvierling 38|20 mm ''Flakvierling'']] quadmount on a [[Panzer IV]] chassis.]]
Larger guns followed on larger trucks, but these mountings generally required off-truck setup in order to unlimber the stabilizing legs these guns needed. One exception to this rule was the Italian [[Cannone da 90/53]] which was highly effective when mounted on trucks, a fit known as the "''autocannoni da 90/53''". The 90/53 was a feared weapon, notably in the anti-tank role, but only a few hundred had been produced by the time of the armistice in 1943.

Other nations tended to work on truck chassis. Starting in 1941, the British developed the "en [[portee]]" method of mounting an anti-tank gun (initially a [[2 pounder]]) on a truck. This was to prevent the weapon from being damaged by long-distance towing across rough, stony deserts, and it was intended only to be a carrying method, with the gun unloaded for firing. However, crews tended to fire their weapons from their vehicles for the mobility this method provided, with consequent casualties. This undoubtedly inspired their Morris C9/B (officially the "Carrier, SP, 4x4, 40 mm AA"), a [[Bofors 40 mm L/60 gun|Bofors 40&nbsp;mm AA gun]] mounted on a chassis derived from the [[Morris C8|Morris "Quad"]] Field Artillery Tractor truck. Similar types, based on 3-ton lorries, were produced in Britain, Canada and Australia, and together formed the most numerous self-propelled AA guns in British service.

The U.S. Army brought truck-towed Bofors 40&nbsp;mm AA guns along with truck-mounted units fitted with mechanized turrets when they sailed, first for Great Britain and then onto France. The turrets carried four .50&nbsp;inch (12.7&nbsp;mm) machine guns, which were designed to be adjusted to converge at the single point where enemy aircraft were expected to appear at low altitude in conduction of strafing runs directed at large infantry and field artillery units.

Interest in mobile AA turned to heavier vehicles with the mass and stability needed to easily train weapons of all sizes. Probably the desire, particularly in German service, for anti-aircraft vehicles to be armoured for their own protection also assisted this trend.

[[File:Nimród Battery 02 (cropped).jpg|thumb|[[40M Nimrod]] anti-aircraft battery.]]
The concept of using armored SPAAG (anti-aircraft tanks) en masse was pioneered by [[Hungary]] during [[World War II]] with the production of the [[40M Nimrod]], a license-produced version of the previously mentioned late 1930s Landsverk L-62 Anti I SPAAG. Germany followed later with their "''Flakpanzer''" series. German World War II SPAAGs include the [[Möbelwagen]], [[Wirbelwind]], [[Ostwind]] and [[Kugelblitz (armoured fighting vehicle)|Kugelblitz]]. Other forces followed with designs of their own, notably the American M16 created by mounting [[M45 Quadmount|quadruple M2HB Browning machine guns]] on a [[M3 Half-track]].

The British developed their own SPAAGs throughout the war mounting multiple machine guns and light cannon on various tank and armoured car chassis and by 1943, the [[Crusader tank|Crusader AA tanks]], which mounted the [[Bofors 40 mm Automatic Gun L/60|Bofors 40 mm]] gun or two-three [[Oerlikon 20 mm cannon]]. Although used during the Normandy landings, by that point German aircraft were contained by the Allies own air forces and they were largely unneeded.